Auxiliary powered forest clearing implement

ABSTRACT

An implement for clearing brush and trees which includes a self-propelled vehicle and at least one boom mounted upon the vehicle. The boom is constructed for articulated motion of a distal end thereof. A cutting disk is operatively mounted for rotation to the distal end of said boom to cut brush and trees when rotated. A secondary power source is supported on the self-propelled vehicle and used to primarily power the cutting disk. The implement is configured to allow field replacement of a cutting wheel support cartridge.

CROSS-REFERENCE TO RELATED CASES

This is a divisional of U.S. patent application Ser. No. 09/861,287,filed May 18, 2001 now U.S. Pat. No. 6,668,880.

TECHNICAL FIELD

The technical field of this invention is implements for clearingvegetative growth, and particularly, implements for clearing densevegetative growth such as brush and trees in forests to build andmaintain around dwellings and roadways, and within utility and othervarious right-of-ways or easements.

BACKGROUND OF THE INVENTION

The public continues to expand the boundaries in which to live by movinginto remote areas of the country with dense vegetation such as forest orwoodlands. The demand to make such remote areas inhabitable requiresclearing the vegetation to allow access for heavy equipment, and tobuild new dwellings, roadways, and right-of-ways. Moreover, existingroadways and right-of-ways have shoulders, banks and drainage ditcheswhich need periodic grooming.

Implements for clearing and grooming such vegetation have been developedutilizing a self-propelled vehicle, such as an excavator backhoe havinga boom apparatus. The boom is pivotally attached to the excavatorturret. The boom apparatus has a distal end with a cutting apparatusattached thereto for cutting and clearing vegetation. The excavator isadvantageously track driven to facilitate transport of the cuttingapparatus to remote locations. The pivoting turret and boom apparatusprovide the cutting apparatus at selective cutting elevations relativeto the ground.

To effectively clear such vegetation, an exemplary implement forclearing and grooming must be capable of providing enough power to thecutting apparatus to sever varying diameters of trees and brush. Suchpower produces detrimental forces to components of the cuttingapparatus. These require routine maintenance, repairs and sometimesmajor overhauls. However, exemplary implements for clearing and groomingare not designed for repairs or overhauls in the field, and aretherefore, transported to a repair shop. If the implement for clearingand grooming is working at an operation site several miles from anaccess road, then considerable time is wasted transporting the excavatoracross rough terrain. Additionally, the transport truck must also travelto the shop after the excavator arrives at the pick-up location wherethe transport truck is to be loaded.

In view of the foregoing, it is desirable to provide an implement forclearing and grooming configured to provide continued operation andcapable of maintenance by operators in the field.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described below withreference to the accompanying drawings, which are briefly describedbelow.

FIG. 1 is a side elevational view illustrating an implement for clearingand grooming according to one preferred embodiment of the presentinvention.

FIG. 2 is a fragmented side elevational view of a distal end of a boomand cutting head according to such embodiment of the present invention.

FIG. 3 is a front elevational view as viewed from the front in FIG. 2.

FIG. 4 is a rear elevational view as viewed from the rear in FIG. 2.

FIG. 5 is the cutting head of FIG. 2 with the cutting head swivelled.

FIG. 6 is the cutting head of FIG. 2 with the cutting head swivelledopposite to FIG. 5.

FIG. 7 is a partial front view of the cutting head of FIG. 2 shownpartially in cross-section taken substantially along line 7—7 in FIG. 2.

FIG. 8 is an exploded view of portions of the FIG. 7 cutting head withcomponents of the cutting head shown removed.

FIG. 9 is a partial side view of FIG. 1 more particularly pointing outand illustrating an auxiliary engine according to a preferred form ofthe present invention.

FIG. 10 is a front elevational view of a front cover for the auxiliaryengine in isolation.

FIG. 11 is a top view of an upper cover for the auxiliary engine inisolation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Vehicle Generally

A preferred embodiment according to the present invention is generallyshown by the reference numeral 10 in the accompanying drawings.Referring to FIG. 1, implement 10 is adapted for clearing and groomingvegetation, such as brush and trees. It includes a self-propelledvehicle 20 and a boom apparatus 70 pivotally mounted to theself-propelled vehicle 20. The boom apparatus has a distal end 90 and acutting head 100 secured to the distal end 90 of boom apparatus 70. Anexemplary self-propelled vehicle 20 may be a 40 ton excavator. It shouldbe understood that an exemplary self-propelled vehicle 20 could includea variety of vehicles adapted for crossing rough terrain found in remoteareas. Furthermore, the exemplary self-propelled vehicle 20 ispreferably capable of traversing terrain having slopes of 50 to 60%relative to horizontal ground 23.

Vehicle Carriage

The vehicle 20 of FIG. 1 includes endless belt or track type groundcontact drives having treads 22 for carrying vehicle 20 over all typesof terrain. A turntable or turret swivel mechanism 24 is mounted on theexcavator carriage in swivelling relation relative to the treads 22 andother parts of the carriage. A turret 25 is mounted on the carriageusing swivel mechanism 24 such that the turret 25 is capable ofswivelling relative to the treads 22 about a swivel axis generallyperpendicular to the terrain 23.

Primary Engine

A main, or primary engine 26 provides power to at least treads 22 tomove vehicle 20 across terrain 23. Moreover, an exemplary primary engine26 provides power to swivel mechanism 24 to swivel turret 25. Primaryengine 26 is mounted, for example, on a rear portion of turret 25. A cab27 is mounted on a front portion of the turret 25, for example; in frontof primary engine 26 to one side of the turret 25. The cab 27 isdesigned to house an operator and includes controls and instrumentationfor operating clearing implement 10.

Secondary Engine

A secondary power source, for example an auxiliary engine 28 (describedmore thoroughly below), is mounted to the turret 25 at the front portionon a side opposite cab 27. Further mounted to the front portion ofturret 25 between cab 27 and auxiliary engine 28 is boom apparatus 70.It should be understood that cab 27, primary engine 26 and auxiliaryengine 28 could be positioned on turret 25 in other configurations withthe previously described orientation only presented as a preferredconfiguration.

Boom Apparatus

The boom apparatus 70 includes at least one boom, with the embodimentshown including a first boom 71 and a second boom 80. It should beunderstood that three or more booms could make up boom apparatus 70 andwould be configured as subsequently described for first and second booms71 and 80. The first boom 71 has a known bent configuration that ensuresthat the second boom 80 clears the vehicle 20 when the first boom 71 isin a vertical position. First boom 71 has a proximal end (not shown)that is pivotally attached to the turret 25 of vehicle 20 as isunderstood in the industry, and a distal end 77.

Boom and Boom Operation

A system for pivoting the boom apparatus 70 includes a hydraulic systemwhich is not shown, but is conventional in the industry. The hydraulicsystem operates boom apparatus 70 preferably using primary engine 26.The boom apparatus 70 pivots between a position in which it extendsgenerally vertical upward from the turret 25, and in a position in whichit extends generally horizontally outwardly from the turret 25. A pairof hydraulic cylinders 72 (only one shown with the other generallyaligned with the one shown on the opposite side of first boom 71 asunderstood in the industry) are pivotally attached to the turret 25 andthe first boom 71 to pivot the first boom 71 between its vertical andhorizontal positions. Each cylinder 72 has a piston 73 that slidinglyextends therefrom and is pivotally attached to the first boom 71 atattachment point, or pivot point 74 located near the bend in the firstboom 71. Additional references to pivot points are made subsequently,and include configurations as is understood in the industry, andtherefore, are not more thoroughly described.

Distal end 77 of first boom 71 is pivotally attached to second boom 80at a pivot point 78 which is spaced from a proximal end 81 of secondboom 80. A hydraulic cylinder 76 is pivotally secured to an uppersurface of the first boom 71, outwardly of pivot point 74, at a pivotpoint 75. The hydraulic cylinder 76 has a piston 79 which slidinglyextends therefrom and is pivotally attached to pivot point 82 located atthe proximal end 81 of second boom 80. Cylinder 76 is operativelyconnected to the hydraulic hose system of clearing implement 10 to pivotthe second boom 80 relative to the first boom 71 about pivot point 78.

Second boom 80 includes a distal end 90 opposite proximal end 81 and ahydraulic cylinder 86 pivotally mounted to an upper surface of secondboom 80 at a pivot point 85. A piston 87 slidingly extends outwardlyfrom cylinder 86 and pivotally engages a linear link pair 88 (only onelink of the pair shown with the other link pivotally connected on theopposite side of second boom 80) at a pivot point 103. Ends of linearlink pair 88 opposite pivot point 103 are pivotally connected to secondboom 80 at a pivot point 102 located a spaced distance from distal end90 of second boom 80. A link plate 91 is pivotally connected at pivotpoint 103 to linear link pair 88 and piston 87. It should be understoodthat link plate 91 could have a one piece link configuration or designedas two links similar to linear link pair 88. An end of link plate 91opposite pivot point 103 is pivotally connected to an actuator mountingplate 105 at a pivot point 101 spaced a distance from the distal end 90of second boom 80.

Rearward of pivot point 101, a rear portion of actuator mounting plate105 is pivotally connected to the distal end 90 of second boom 80 at apivot point 104 such that actuator mounting plate 105 extends outwardlyfrom pivot point 104. Linear link pair 88 and plate link 91 areconfigured with pivot points 101, 102, 103 and 104 such that actuationof piston 87 by hydraulic cylinder 86 drives actuator mounting plate 105to selectively pivot same relative second boom 80 about pivot point 104.Hydraulic cylinder 86 is operatively connected to primary engine 26 viathe hydraulic hose system.

Cutting Head

Referring to FIGS. 2–8, a cutting head 100 is more thoroughly described.Referring to FIG. 2, cutting head 100 includes a cylindrical cuttinghead swivel, or hydraulic rotary actuator 107 oriented generallylongitudinally parallel and beneath actuator mounting plate 105. A pairof clamps 106 secure hydraulic rotary actuator 107 to actuator mountingplate 105. Hydraulic rotary actuator 107 is rotationally connected to acutting head frame 110 between a rearward end 108 and a forward end 109of cutting head frame 110. Actuation of hydraulic rotary actuator 107produces a selective swivel action of cutting head frame 110 about aswivel axis oriented along the longitudinal axis of hydraulic rotaryactuator 107 and generally traversing the pivot axis of pivot point 104.Referring to FIG. 3, swivel action is generally indicated by arrow 144,and alternatively, arrow 145, both shown in phantom. FIG. 5 illustratescutting head 100 swivelled according to arrow 144 and FIG. 6 illustratescutting head 100 swivelled according to arrow 145.

Referring to FIGS. 2 and 4, rearward end 108 extends generallydownwardly from hydraulic rotary actuator 107 and terminates into alower end 111. A jaw 113 is pivotally connected to lower end 111 ofrearward end 108 at a pivot point 112. Jaw 113 includes an extensionplate 114 extending outwardly of pivot point 112 and terminates to forma serrated plate 115 oriented generally perpendicularly to extensionplate 114. Serrated plate 115 extends forward of extension plate 114 andterminates to form a first set of teeth 115 a, and extends rearward ofextension plate 114 and terminates to form a second set of teeth 115 b.The second set of teeth 115 b act as a rake when pivoting actuatormounting plate 105 about pivot point 104 wherein the second set of teeth115 b pivot with cutting head frame 110 to provide a selective rakeaction across terrain 23. Extension plate 114 further defines a pivotpoint 126 spaced generally forward and below pivot point 112 and whichprovides a pivotal connection to a piston 125. Piston 125 slidinglyextends from a hydraulic cylinder 123 pivotally connected to a bottomsection 118 of cutting head frame 110.

A shroud 117 is mounted to the bottom section 118 of cutting head frame110 and extends downwardly therefrom generally in front and belowhydraulic cylinder 123. Shroud 117 defines a back section 120 extendingtoward serrated plate 115 wherein back section 120 terminates to form athird set of teeth 116 configured to engage in complementary fashion thefirst set of teeth 115 a. Such engagement defines a first closedposition of jaw 113. Particularly referring to FIG. 2, activation ofhydraulic cylinder 123 selectively extends and retracts piston 125 topivot jaw 113 about pivot point 112 between the first closed position(shown in solid lines), and alternatively, a second open position 122,shown in phantom. Accordingly, jaw 113 and third set of teeth 116cooperate relative one another to provide a grasping action for debrisand severed vegetation.

Referring to FIG. 2, a front section 127 of shroud 117 defines an opensection to house a portion of a cutting disk 140. Cutting disk 140 isrotatably mounted to cutting head frame 110 below bottom section 118 ata forward end 109. A hydraulic motor 128 is secured to cutting headframe 110 above forward end 109 to drive cutting disk 140 rotationally.Hydraulic motor 128 is operatively connected to auxiliary engine 28 forpower. It is preferred to devote all or substantially all of the powerto the cutting wheel to provide substantially enhanced performance. Itshould be understood that in less preferred configurations the hydraulicrotary actuator 107 and hydraulic cylinder 123 could be powered byauxiliary engine 28, or primary engine 26, or combinations thereof.

The hydraulic system powering the cutter preferably is provided with anoil cooler for cooling the hydraulic drive. This can be a fan andradiator combination 337 (See FIG. 10). The hydraulic oil cooler ispreferably in side-by-side relationship to the auxiliary engine coolantradiator 338. This configuration allows the hydraulic oil to be bettercooled in view of the high power of the cutter drive.

Referring to FIGS. 3 and 5, cutting disk 140 defines an upper face 141which includes a plurality of removably secured cutting and grindingdevices 143 extending therefrom. Referring to FIGS. 3 and 6, cuttingdisk 140 defines a lower face 142 which includes a plurality ofremovably secured cutting teeth and/or grinding or comminuting devicesor features 143 extending therefrom. Furthermore, some of such cuttingand grinding devices 143 extend outwardly of a periphery 148 of cuttingdisk 140 to define a periphereal cutting area.

Cutter Drive

Referring to FIGS. 7 and 8, cutting disk 140 and components that drivesame are described more thoroughly. Beginning at the bottom of FIG. 7, afragmented view of cutting disk 140 is illustrated with cutting andgrinding devices 143 removed. Cutting disk 140 is secured to a hub 178by threaded members 180 extending through cutting disk 140 and alaterally extending flange region 179 of hub 178. Hub 178 is rotatablysecured to forward end 109 of cutting head frame 110 by a bearingmechanism, or main bearing (detailed components not illustrated) housedinside the forward end 109 of cutting head frame 110. Actual componentsof main bearing are not shown nor described as such is understood andconventional in the art. However, a main bearing housing, or cartridge177 for enclosing the main bearing is illustrated.

Cutter Drive Cartridges

Cartridge 177 includes a first portion 176 which extends through anopening 175 in cutting head frame 110. Flanges 181 extend laterallyoutwardly from first portion 176 and are positioned adjacent to cuttinghead frame 110 such that threaded members 182 extend through flanges 181into cutting head frame 110 to secure cartridge 177 to cutting headframe 110. A second portion 183 of cartridge 177 extends upwardly fromthe first portion 176 and defines a smaller cross-sectional dimensionthan the first portion 176 and is completely housed in the forward end109 of cutting head frame 110.

An upper end of second portion 183 abuts against a mating plate 184 andis secured thereto by threaded members 189 extending through matingplate 184 into aligned bores 188 formed in second portion 183. Thecross-sectional dimension of mating plate 184 is larger than thecross-sectional dimension of second portion 183 to extend outwardly ofopposite sides of second portion 183 and rest on shoulders 185 extendinginwardly from an inner wall 186 of cutting head frame 110. Threadedmembers 187 secure mating plate 184 to shoulders 185.

A drive shaft, or first shaft 190 includes a first portion 191 that issecured to hub 178. As shown, shaft 191 has a boss or flange 391 at thedistal end which mates with a stepped receptacle 392 formed in part 179and extends from cartridge 177 through mating plate 184. A secondportion 192 of first shaft 190 extends upwardly from first portion 191and into a first sprocket 193. First sprocket 193 defines sprocket teeth194 extending radially outwardly to receive a portion of a drive chain195. Spaced above and aligned with first sprocket 193 is a secondsprocket 196 defining sprocket teeth 196 a extending radially outwardlyto receive another portion of drive chain 195 wherein first sprocket 193is coupled to second sprocket 196. Sprocket teeth 196 a of secondsprocket 196 are formed on a terminal end of a hydraulic motor shaft 197wherein hydraulic motor shaft 197 is driven rotationally by hydraulicmotor 128 as is understood in the industry, and therefore, is notdescribed.

Cutter Drive Connection

It should be understood that second portion 192 of first shaft 190 iskeyed into first sprocket 193 as understood in the art, and FIG. 8illustrates an exemplary key opening 198, such as a longitudinal slot,in second portion 192 of first shaft 190 to receive a key extension, ornodule (not shown) formed on an inside wall of first sprocket 193. Suchkey configuration will allow first shaft 190 to be released downwardfrom first sprocket 193 without removing drive chain 195 to uncouplefirst and second sprockets 193 and 196.

A portion of forward end 109 defines an opening 172 for access to drivechain 195 and threaded members 189. A door or cover 173 is secured toforward end 109 of cutting head frame 110 by threaded members 174 toprotect the inside of forward end 109 from the outside environment.

Cartridge Changing

Referring to FIG. 8, an exemplary method of removing cartridge 177,first shaft 190 and hub 178 as a unit is illustrated. It should beunderstood that cutting disk 140 has already been removed from hub 178by removing threaded members 180 (see FIG. 8). It should further beunderstood cutting disk 140 can be removed at any stage of the exemplarysequence of steps described subsequently. Alternatively, cutting disk140 could remain secured to hub 178 and be removed with the unit. First,threaded members 174 are removed so door 173 can be separated fromcutting head frame 110 to provide access to opening 172.

One exemplary method includes removing threaded members 189 fromthreaded bores 188 to release second portion 183 of cartridge 177 frommating plate 184. Next, in one exemplary method, threaded members 182can be removed from flanges 181 of first portion 176 and cutting headframe 110 to release first portion 176 from cutting head frame 110allowing cartridge 177, first shaft 190 and hub 178 to be unleashed as aunit from forward end 109 of cutting head frame 110. It should beunderstood that this is only one exemplary method of removing the unitand that any combination of these steps could be performed in any order.

Alternatively, first portion 176 of cartridge 177 could be released fromthe cutting head frame 110 before removing door 173.

Furthermore, second portion 192 of first shaft 190 could define anotherkey configuration such that first shaft 190 cannot be released fromfirst sprocket 193 by simply applying a downward force on the unit, andtherefore, drive chain 195 may need to be removed to unleash firstsprocket 193 with the unit. If so, it should be understood that drivechain 195 is released from first and second sprockets 193 and 196 byremoving a master link 199 as is understood in the art. Moreover, drivechain 195 could be removed before or after threaded members 189 arereleased from second portion 183 and mating plate 184. It should beunderstood that any combination of these steps could be performed in anysuitable order to effect the indicated disconnection.

Auxiliary Engine

Referring to FIG. 9, a larger fragmented view of FIG. 1 is shown tofacilitate a more thorough description of auxiliary engine 28. A steelframe 240 surrounds auxiliary engine 28 and is partially broken away tomore thoroughly show components of engine 28. An upper cover, or topsteel cover 241 protects an upper portion of auxiliary engine 28. Uppercover 241 defines an upper surface 242 which has alternating angled andgenerally horizontal portions relative to terrain 23 to establish stepswhich increase in elevation as upper cover 241 extends from the rear ofturret 25 toward the front. It should be understood that the uppersurface 242 of upper cover 241 may comprise configurations other thanthe stepped configuration shown, such as, a generally horizontal uppersurface relative terrain 23.

An exemplary upper cover 241 includes a front portion 243 pivotallyconnected to frame 240 (not shown) to allow upper cover 241 to bepivoted upward when access to upper portion of auxiliary engine 28 iswarranted. Referring to FIG. 11, the upper surface 242 of top cover 241is more thoroughly shown defining a plurality of square openings 244with each covered by a screen 245 to allow dissipation of heat fromauxiliary engine 28 and viewing therein. Also shown is a circularopening 246 which may be used, for access to the radiator cap (notshown).

Referring to FIG. 9, a front cover, or louver 220 is generally indicatedat a front portion of auxiliary engine 28, and referring to FIG. 10,louver 220 is shown in detail. Louver 220 is attached to frame 240 by aplurality of hinges 223. Louver 220 comprises a steel frame 221 withfins 224 extending generally horizontally between portions of frame 221.Fins 224 are slanted downward to provide ventilation, and to excluderain and other debris from reaching auxiliary engine 28 from the front.

In compliance with the statute, the invention has been described inlanguage necessarily limited in its ability to properly convey theconceptual nature of the invention. Because of this inherent limitationof language, it must be understood that the invention is not necessarilylimited to the specific features described, since the means hereindisclosed comprise merely preferred forms of putting the invention intoeffect.

1. An implement for clearing brush and trees, comprising: a cutting headhaving a cutting head frame; a motor mounted to the cutting head frame;a drive shaft operatively coupled to the motor for rotation; said driveshaft constructed to be selectively uncoupled from the motor; a bearingmechanism removably secured to the cutting head frame and supporting thedrive shaft for the rotation; a cutting disk mounted on the drive shaftfor rotation therewith; and wherein the bearing mechanism is held by atleast one detachable securement member which can be detached to allowthe bearing mechanism to be detached from the cutting head to facilitatereplacement of the bearing mechanism and drive shaft.
 2. An implementaccording to claim 1 wherein the bearing mechanism and drive shaft areconstructed to be detached from the cutting head as a unit.
 3. Animplement according to claim 1 and further comprising: cutting headteeth formed in a rearward portion of the cutting head; and a pivot jawpivotally mounted to said cutting head frame for selective pivotalmovement relative to said cutting head teeth to allow controlledgrasping action between said cutting head teeth and said pivot jaw. 4.An implement according to claim 3 and further comprising: a hydrauliccylinder having a first end pivotally connected to the cutting headframe; and a piston slidingly extending from an opposite second end ofthe hydraulic cylinder; said piston having a distal end pivotallyconnected to the pivot jaw wherein actuation of the hydraulic cylinderdrives the piston to provide pivotal movement of the pivot jaw relativeto the cutting head teeth.
 5. An implement according to claim 1 whereinthe bearing mechanism comprises a first portion, and a second portionextending longitudinally from the first portion; said first portion isremovably secured to the cutting head frame by a first set of securementmembers and said second portion is removably secured to the cutting headframe by a second set of securement members; and wherein removing saidfirst and second sets of securement members releases the drive shaft andbearing mechanism from the cutting head frame as a unit.
 6. An implementaccording to claim 5 wherein said first set of securement members areaccessible from outside the cutting head frame; and wherein said secondset of securement members are housed within a portion of the cuttinghead frame and accessible from an opening in the cutting head frame. 7.An implement for clearing brush and trees, comprising: an articulatedboom adapted for movement of a distal end thereof; a cutting head havinga cutting head frame mounted upon the articulated boom to allowadjustable positioning of the cutting head; a motor mounted upon thecutting head having a rotatable motor shaft; a bearing cartridge whichis detachable from the cutting head and having a drive shaft which isrotatable relative to a bearing cartridge housing, said bearingcartridge being adapted to be coupled to and uncoupled from the cuttinghead and motor shaft; at least one detachable securement member whichcan be attached to or detached from the cutting head to allow thebearing cartridge to be attached or detached, respectively, from thecutting head to facilitate replacement of the bearing cartridge anddrive shaft.
 8. An implement according to claim 7 further comprising apivotal jaw mounted at a rearward position upon the cutting head toallowing controlled grasping action.
 9. An implement according to claim8 wherein said pivot jaw is operated by a hydraulic operator.
 10. Animplement according to claim 7 having a pivotal jaw mounted at arearward position upon the cutting head to allowing controlled graspingaction with complementary teeth.
 11. An implement according to claim 7wherein the bearing cartridge comprises a first portion, and a secondportion extending longitudinally from the first portion; said firstportion is removably secured to the cutting head by a first set ofsecurement members and said second portion is removably secured to thecutting head by a second set of securement members.
 12. An implementaccording to claim 7 wherein the bearing cartridge comprises a firstportion, and a second portion extending longitudinally from the firstportion; said first portion is removably secured to the cutting head bya first set of securement members and said second portion is removablysecured to the cutting head by a second set of securement members; saiddrive shaft being connected to the motor shaft using a chain.
 13. Animplement according to claim 7 wherein the bearing cartridge comprises afirst portion, and a second portion extending longitudinally from thefirst portion; said first portion is removably secured to the cuttinghead by a first set of securement members and said second portion isremovably secured to the cutting head by a second set of securementmembers; said drive shaft being connected to the motor shaft using achain which engages with sprockets on the motor shaft and drive shaft.14. An implement according to claim 7 said drive shaft being connectedto the motor shaft using a chain.
 15. An implement according to claim 7said drive shaft being connected to the motor shaft using a chain whichengages sprockets on the motor shaft and drive shaft.
 16. An implementaccording to claim 7 wherein said at least one detachable securementmember includes: one or more securement members connecting upperportions of the bearing cartridge to the cutting head; one or moresecurement members connecting lower portions of the bearing cartridge tothe cutting head.
 17. An implement according to claim 7 wherein said atleast one detachable securement member includes: one or more securementmembers connecting upper portions of the bearing cartridge to thecutting head; one or more securement members connecting lower portionsof the bearing cartridge to the cutting head; said securement membersconnecting upper portions and said securement members connecting lowerportions are in opposing relationship.
 18. A method for changing abearing cartridge on an implement for clearing brush and trees which hasa cutting head with a motor and motor shaft which drive a drive shaft,comprising: uncoupling a drive shaft of a first bearing cartridge fromthe motor shaft; detaching securement members holding the first bearingcartridge in place relative to the cutting head; removing the firstbearing cartridge; placing a second bearing cartridge into the cuttinghead; attaching securement members to the second bearing cartridge tosecure the second bearing cartridge in place relative to the cuttinghead; coupling the drive shaft of the second bearing cartridge to themotor shaft.
 19. A method according to claim 18 wherein the uncouplingand coupling steps use a chain.
 20. A method according to claim 18wherein the uncoupling and coupling steps use a chain which engages withsprockets on the motor shaft and drive shafts of the first and secondbearing cartridges.